DVR-MS, also called Microsoft Digital Video Recording, is a digital audio and video file container format introduced by Microsoft in 2004. It features a .dvr.ms filename extension and is used to save TV data recorded using Windows 7, Windows Vista, and Windows XP Media Center Edition. It stores both audio and video data wrapped inside an ASF container.
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M4A is a filename extension for AAC container format and is developed by Apple Inc. M4A music is bought on the iTunes Store and does not come with DRM protection. In terms of quality, M4A is better than MP3 because it is lossless but still compressed. This means that it occupies less storage space and doesn’t lose quality over time.
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